In a thin film transistor liquid crystal display (TFT-LCD) device, a gamma curve is used to represent the relationship between pixel voltage and pixel brightness. In the liquid crystal display panel, the gamma curve under a central viewing angle is different from that under a squint viewing angle. In this case, color cast would occur to the liquid crystal display panel viewed in a squint angle, and the liquid crystal display panel would appear white-ish. Consequently, the image display effect is influenced. The above problem should be eliminated.
In order to eliminate color cast, a subpixel 1 in a pixel is usually divided into two equal parts, namely part 1A and part 1B as shown in FIG. 1. As shown in FIG. 2, when the liquid crystal display panel is driven, a thin film transistor (TFT) of a first scan line G1 is enabled first, so that a drive voltage can charge parts 1A and 1B with the same amount of electric charges through a data line D, whereby parts 1A and 1B can have the same voltage V1. Subsequently, a portion of the electric charges of part 1B are discharged through a second scan line G2, so that a voltage difference ΔV can be generated between parts 1A and 1B. In this case, voltage of part 1A is higher, thus forming a higher gray scale; and voltage of part 1B is lower, thus forming a lower gray scale. The higher gray scale and the lower gray scale are mixed to form a medium gray scale, so that the gamma curve under the squint viewing angle can be close to that under the central viewing angle, whereby color cast can be alleviated. However, a gate switch should be added in the above design, causing the production cost of the display panel to increase. In the meantime, the discharging procedure of part 1B renders the time for charging and discharging the pixel to increase.